This study is documenting the rates of breast and bottle feeding among different Bedouin tribes who are residing in the Negev. These tribes are changing at various rates from a nomadic to a seminomadic and to a sedentary life style. Another objectives is the evaluation of the effect of differences in infant feeding practices during the first year of life on physical growth of the children and on morbidity especially respiratory and gastrointestinal disease during the first year of life. Data have been collected on about 5,000 infants. Twenty five hundred were identified at birth with a subsample followed for a period of from 5-8 months. Another sample identified children at 6 months of age and obtained infant feeding histories retrospectively prior to 6 months with a follow-up of a sample of these children to 18 months of age. The information collected include demographic data about the mother and information about the tribe and it's life style, medical and reproductive history as well as information on events surrounding the peroid of birth including complications. Information about the children in the study include neonatal conditions and problems, infant feeding practices and changes over time during the first year of life and data on child rearing practices, morbidity and various measures of physical growth of the children. The data collection is complete and the information collected has been computerized. Considerable problems were countered in cleaning up the tape and involved numerous interactions with the Beer Sheva group. Data analysis is in progress with three papers from these data to be presented at one international and one national meeting in 1985.